The present invention relates to a wireless communication apparatus, a system, and a method. For example, the present invention relates to a wireless communication apparatus, a system, and a method that are suitable for establishing steady communication by using a redundant configuration.
Due to widespread use of wireless communication apparatuses, a plurality of wireless communication apparatuses may autonomously establish coupling to form a tree or mesh wireless network. In this instance, a wireless communication apparatus coupled to an external network operates as a mission-critical wireless communication apparatus, which is important in a wireless network, and has a significant influence on communication stability.
If the mission-critical wireless communication apparatus in the wireless network becomes faulty, the mission-critical wireless communication apparatus interrupts communication so as to impair the functions of the whole wireless network. This situation is avoided by a known method in which, for example, a substitute (redundant) wireless communication apparatus is provided and used to rebuild the wireless network and restore the communication functions of the whole wireless network.
However, rebuilding the wireless network requires the use of a large amount of communication resources such as radio resources and power resources in order to permit the wireless communication apparatuses to exchange a large number of communication packets. As the radio resources and the power resources for the wireless communication apparatuses are limited, rebuilding the wireless network imposes a significant load on the wireless network and the wireless communication apparatuses. Therefore, when the mission-critical wireless communication apparatus in the wireless network becomes faulty, it is demanded that communication be maintained unaffected without rebuilding the wireless network.
Disclosed in Japanese Unexamined Patent Application Publication No. 2008-283608 is a technology in which an active interface and a standby (redundant) interface each use a unique address to transmit a diagnostic packet and monitor the status of a communication path. If the communication path coupled to the active interface becomes abnormal, the disclosed technology uses the standby interface. However, Japanese Unexamined Patent Application Publication No. 2008-283608 does not describe a method of maintaining communication unaffected in the event of a fault in a wireless communication apparatus by taking over, for example, wireless communication coupling information.
Disclosed in Japanese Unexamined Patent Application Publication No. 2009-027758 is an aggregation function that is exercised in a network relay device having a plurality of physical ports in order to bundle the physical ports and handle them as a single logical port. However, Japanese Unexamined Patent Application Publication No. 2009-027758 does not describe a method of maintaining communication unaffected in the event of a fault in a wireless communication apparatus by taking over, for example, wireless communication coupling information.